System, method, and apparatus to provide laser beams of two or more wavelengths

ABSTRACT

A system, apparatus, and method may provide laser beams of two or more wavelengths from diode pumped solid-state laser sources ( 220, 222, 224 ). The beam paths of these laser beams with different wavelengths, which are generated by the laser sources ( 220, 222, 224 ), may be aligned along a common optical axis  280  by an optical configuration, to treat at least one target area. Frequency-doubled laser beams, output from a plurality of diode pumped solid state laser cavities, may be passed through fold mirrors (M 2 , M 5 , M 8 ), and combined on a common optical axis  280 , using one or more combiner mirrors (M 10 , M 11 , M 12 ), to unify the beam paths. Selected laser beams may be delivered to a target using one or more delivery systems.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication 60/418,719, filed 17 Oct. 2002, entitled “Three-color, diodepumped solid state ophthalmic laser device”, which is incorporated inits entirety herein by reference.

FIELD OF ME INVENTION

Embodiments of the present invention relate generally to laser devicesand methods, and more particularly to systems, methods and apparatusesthat provide two or more laser beams of different wavelengths.

BACKGROUND OF THE INVENTION

Intense light energy, such as a laser beam, can be used forphotocoagulation and endo-photocoagulation, for example, to performsurgical coagulation of tissue to destroy abnormal tissues or to formadhesive scars, especially in ophthalmology. Diode-pump solid state(DPSS) lasers, which are known and are used in many applications, forexample, in treatment by illumination of body tissue, are increasinglybeing used for precision, fine machining procedures and treatments.

Pumped-light laser sources, e.g., diode lasers, are generally moreefficient than conventional laser sources. DPSS lasers are particularlyuseful because they can be designed to emit at essentially anywavelength within a wavelength range determined by the specificsemiconductor materials used for their manufacture.

SUMMARY OF THE INVENTION

There is provided, in accordance with an embodiment of the presentinvention, an apparatus, system, and method to provide laser beams oftwo or more wavelengths from two or more diode pumped solid state (DPSS)laser sources. According to some embodiments of the present invention, alaser illumination system that includes a laser sub-system may beprovided. For example, the laser sub-system may include a module withtwo or more DPSS laser cavities to produce beams of two or morerespective wavelengths, and an optical configuration to align the pathsof these two or more laser beams along a common optical axis using, forexample, fold mirrors and combiner mirrors.

In accordance with an embodiment of the present invention, an opticssub-system may be used to control and channel selected laser beams, forexample, laser beams of two or more respective wavelengths, to one ormore delivery systems. One or more delivery systems may deliver thelaser beams to one or more selected targets.

Furthermore, in accordance with an embodiment of the present invention,a method is provided to produce laser hems of two or more wavelengthsfrom two or more DPSS laser sources, align the paths of the laser beamsalong a common optical axis, and select at least one laser beam with adesired wavelength to deliver to at least one target area. Such a methodmay include combining the paths of frequency-doubled light beams fromtwo or more diode pumped solid state laser cavities on a substantiallycommon optical axis.

In accordance with an embodiment of the present invention, a method isprovided to operate the laser illumination system, at one or morewavelengths selected from two or more wavelengths generated by, two ormore respective DPSS laser cavities.

BRIEF DESCRIPTION OF THE DRAWINGS

The principles and operation of the system, apparatus, and methodaccording to the present invention may be better understood withreference to the drawings, and the following description, it beingunderstood that these drawings are given for illustrative purposes onlyand are not meant to be limiting, wherein:

FIGS. 1A and 1B are a schematic block diagram illustration of anexemplary illumination system, according to at least one aspect of anembodiment of the present invention;

FIG. 2A is a schematic illustration of a laser sub-system of theillumination system of FIG. 1, according to some exemplary embodimentsof the present invention;

FIG. 2B is a schematic illustration of an optics sub-system of theillumination system of FIG. 1, according to some exemplary embodimentsof the present invention;

FIG. 3 is a is a flowchart illustration of an exemplary method forgenerating and delivering DPSS laser beams of two or more wavelengths bythe laser illumination system of FIG. 1; and

FIG. 4 is a flowchart illustrating an exemplary method for operating alaser illumination system at one or more selected wavelengths inaccordance with embodiments of the present invention.

It will be appreciated that for simplicity and clarity of illustration,elements shown in the drawings have not necessarily been drawn to scale.For example, the dimensions of some of the elements may be exaggeratedrelative to other elements for clarity. Further, where consideredappropriate, reference numerals may be repeated among the drawings toindicate corresponding or analogous elements throughout the serialviews.

DETAILED DESCRIPTION OF THE INVENTION

The following description is presented to enable one of ordinary skillin the art to make and use the invention as provided in the context of aparticular application and its requirements. Various modifications tothe described embodiments will be apparent to those with skill in theart, and the general principles defined herein may be applied to otherembodiments. Therefore, the present invention is not intended to belimited to the particular embodiments shown and described, but is to beaccorded the widest scope consistent with the principles and novelfeatures herein disclosed. In other instances, well-known methods,procedures, and components have not been described in detail so as notto obscure the present invention.

Embodiments of the present invention may enable an apparatus, system,and method for selectively providing beams of two or more wavelengthsgenerated by two or more independent DPSS laser sources.

Reference is now made to FIGS. 1A and 1B, which schematically illustratean exemplary laser illumination system 100, according to at least oneaspect of an embodiment of the present invention. As can be seen in FIG.1A, laser illumination system 100 may include a user interface 105 toenable a user to operate system 100, a controller 107 to controloperation of system 100, and a laser control sub-system 140 to controlthe laser energy provided by a laser sub-system 150. Laser sub-system150 may enable generation of laser beams of two or more wavelengths bytwo or more respective laser cavities, and align the paths of theoutputted laser beams with differing wavelengths along a common opticalaxis. As can be seen in FIG. 1B, system 100 may further include anoptics sub-system 165, to control, channel and deliver selected laserbeams to one or more selected targets.

User interface 105 may include, for example, a control and display panel106, which may include, for example, a LCD display device, a touchscreen interface, and any other suitable associated input devices, toenable a user to operate system 100. User interface 105 may furtherinclude a remote control unit 104, a footswitch 108, and additionalinteractive controls, such as input and output devices, to enable auser, such as a medical practitioner, to interface with system 100.Additional components of user interface 105 may include one or more eyesafety filters 109, BRH plug 113, printer 111, at least one serial port112, and/or operating software. Other activation means, components,units, and/or accessories etc. may be used.

Controller 107 may include a processor or CPU 110 with controlelectronics, to enable data processing and control of system 100. CPU110 may include hardware, an embedded micro controller, and/or software,etc., to control and monitor functions within laser illumination system100, and to control user initiated instructions. In addition, hardwareand/or software for monitoring laser safety critical functions, as areknown in the art, may be integrated into CPU 110. CPU 110 may include amemory unit 115, which may store, for example, system data andexecutable code for operating system 100. Controller 107 may include asystem logic device, such as, for example, an electrically programmablelogic device (EPLD) 120, or any other suitable component, to enableprogramming and execution of system logic according to usagerequirements. CPU 110 may be adapted to process results of actual laserbeam output, for example, from a main photocell or detector 167 and/or asafety photocell 168 in optics sub-system 165, as described in detailbelow. CPU 110 may utilize such processed data to instruct laser controlsub-system 140 to adjust the outputs of laser cavities 152, 154 and/or156 to achieve a desired laser beam output.

System 100 may include a power supply 130 to supply the electric powerto the system 100 or part thereof. For example, power supply 130 maycontrol voltage supplied to CPU 110 or to components of laser controlsub-system 140 etc. A cooling unit 125 may be provided to coolcontroller 107 or part thereof, as well as to cool components of a pumpdiode current control unit 141.

Laser control sub-system 140, the operation of which may be controlledby CPU 110, may control laser energy generation by, for example, lasercavities 152, 154, and 156. Laser control sub-system 140 may includepump diode current control unit 141 to control the provision of electriccurrent to laser cavities 152, 154, and 156, respectively, using a fieldeffect transistor (FET) gate. Laser control sub-system 140 may includeat least one TEC control unit, such as, for example, a red TEC controlunit 142, a yellow TEC control unit 143, and a green TEC control unit144, to provide precise temperature control for enabling stable laseroutput from laser cavities 152, 154, and 156, respectively. Such TECcontrol units may control respective thermo-electric (1E) cooler units,for example, TE cooler units 153, 155 and 157 located in laser capsules152, 154 and 156, respectively. TEC control units 142, 143 and 144 mayreceive feedback, for example, temperature sensing data, from TE coolerunits 153, 155 and 157 respectively.

Laser sub-system 150 may include two or more laser cavities, forexample, cavities 152, 154 and 156, to generate light beams of differentwavelengths. Cavities 152, 154 and 156 may include, for example, red,yellow, and green diode pumped solid-state laser sources and respectivefrequency doubling sections, as are described in detail below. Cavities152, 154 and 156 may be associated with TE coolers, for example, coolers153, 155 and 157, respectively. Laser sub-system 150 may further includean optical configuration 160 to align the paths of the outputted laserbeams along a common optical axis, as is described in detail below.

Optics sub-system 165, which may be used to control, channel and deliverselected laser beams to one or more selected targets, may include anattenuator 169 to attenuate outgoing pulses, and/or a shutter 170 tocontrol or limit outgoing laser pulses. Optics sub-system 165 mayfurther include at least one power-monitoring device, such as, forexample, main photocell 167 and safety photocell 168, which are capableof sampling the output energy of outputted laser beams. Sampled data,for example, may be transferred from main photocell 167 and/or safetyphotocell 168 to controller 107, where the data may be processed. Opticssub-system 165 may further include an aiming laser 175, such as, forexample, a diode aiming beam laser, to enable a user of system 100 toaim laser pulses at one or more targets, as is known in the art. Opticssub-system 165 may include an output selector 180 to select desiredlaser beam outputs. One or more optical ports, such as optical ports 185and 186, may be provided to channel outputted laser beams to one or moredelivery systems 190. Delivery systems 190, which may include opticalfibers, may enable delivery of two or more beams of differentwavelengths to different targets, for example, in an ophthalmic tissueof a patient 195.

An exemplary embodiment of an aspect of the present invention mayinclude two or more laser diodes, for example, three diode pumped solidstate (DPSS) laser sources, within laser cavities 152, 154 and 156,which may provide, for example, green, yellow, and red laser beams. Insome exemplary embodiments the laser beam wavelengths that may be outputby system 100 may include wavelengths of about 532 mm, about 561 nm, andabout 659 nm. Other structures and dimensions may be used, for example,to provide different wavelength values, a different number of differentwavelengths and/or desired combinations of one or more wavelengths

Delivery systems 190 may include, for example, standard commerciallyavailable Zeiss style examination slit lamp(s), endoprobes, and indirectopthalmoscopes etc. Delivery systems 190, which may be constructed fromfiber optics or other optical media, may be attached to user interface105 at either or both of optical ports 185 and 186 etc. Examples ofdelivery devices that may be used in conjunction with embodiments of thepresent invention may include Laserlink-Z, manufactured by Lumenis Inc.,2400 Condensa St., Santa Clara, Calif. 95051, USA; Laser Indirect,manufactured by Lumenis Inc.; Opthalmascope, manufactured by LumenisInc.; and Acculite Probe, also manufactured by Lumenis Inc.

User interface 105, controller 107, laser control sub-system 140, lasersub-system 150, optics sub-system 165, power supply 130, cooling unit125, and any other modules, devices, units and/or sub-systems mayoperate independently, interdependently, or in any combination.

FIG. 2A is a schematic illustration of a top view of laser sub-system150, according to some embodiments of the present invention. Lasersub-System 150 may include intra-cavity optics 210, which may includeone or more independent diode pumped solid-state laser cavities, forexample, laser cavities 220, 222 and 224. Laser cavities 220, 222 and224 may include independent pump diode laser sources 212, 214 and 216,respectively. These pump diode laser sources may be composed, forexample, from Gallium Arsenide (GaAs), InGaAP InGaAsP, AlGaAs, or othersuitable compounds. Diode lasers (e.g., DL-1, DL-2, DL-3) may serve aspump sources to emit nominal light, for example at about 808 nm, that isdirected into a laser rod, for example Nd:YAG-1, Nd:YLF, Nd:YVO4,Tm:YAG, Cr:LiSAF, Er:YAG, Ti:Sapphire, Yb:SFAP or other suitable laserrods, to populate the lasing levels of the laser rods. This pumping maybe accomplished, for example, by controlling the electrical powersupplied to the diode pump lasers. Alternative pumping sources may beused. Each individual laser cavity may include a primary laser section,for example sections 206, 207, 208, including, for example, a laser rod(e.g., Nd:YAG-1, Nd:YAG-2, or Nd.YAG-3) to pump the initial light energyfrom the diodes; a frequency doubling section, for example sections 226,227 and 228, including respective frequency doubling elements, such as,for example KTP crystals (e.g., KTP-1, KTP-2, and KTP-3), BBO, LBO, KN,LiNbO3, MgO:LiNbO3 or other suitable frequency doubling elements;mirrors (e.g., M1 to M9) and lenses (e.g., L1, L2 and L3). Lasercavities 220, 222 and 224 may respectively enable generation of laserbeams at precise predetermined wavelengths, for example, about 532 nm,about 561 nm, about 659 nm, and/or any other desired laser wavelengths.

Laser cavities 220, 222 and 224, for example, may be arranged in afolded configuration. Each cavity may be defined, for example, by threemirrors: two highly reflective end mirrors (e.g., M1, M3, M4, MG, M7,and M9), and a central output fold mirror (e.g., M2, M5, and M8) thatmay be partially transmissive at the desired wavelength. In exemplaryembodiments of the present invention cavity mirrors M1, M3, M4, M6, M7,and M9 may be designed to be highly reflective to a fundamental infraredwavelength and to the frequency-doubled wavelength. The fold mirror foreach cavity, e.g., M2, M5, and M8, may additionally be coated with asuitable material to be partially transmissive to the frequency-doubledlaser beam outputs, and thereby to serve as an output coupler, as isknown in the art.

In the example described herein, the green laser source 212 may use, forexample, an Nd:YAG rod to produce a fundamental wavelength of about 1064nm. This wavelength may have the highest gain of the available nearinfrared Nd:YAG wavelengths. The green cavity mirrors (e.g., M7, M8, andM9) may therefore require no suppression of the reflectivity of otherpotentially competing transitions. Part of the 1064 nm light within thegreen laser cavity 220 may be converted to about 532 nm by the frequencydoubling section 226. This 532 nm (green) light may be extracted fromthe green laser cavity 220 by partial transmission through the greenlaser output fold mirror M8. Other wavelengths in the green spectrum maybe used, and other laser sources may be used.

In the example described herein, the red laser source 214 may use, forexample, Nd:YAG rod to produce a fundamental wavelength of about 1319nm. The red cavity mirrors (e.g., M1, M2, and M3) may be highlyreflective at 1319 nm, but may suppress the reflectivity of other nearinfrared wavelengths. Part of the 1319 nm light within the red lasercavity 224 may be converted to about 659 nm by the frequency doublingsection 228. The 659 nm (red) light may be extracted from the red lasercavity 224 by partial transmission through the red laser output foldmirror M2. Other wavelengths in the red spectrum may be used, and otherlaser sources may be used.

In the example described herein, the yellow laser source 222 may use,for example, an Nd:YAG rod to produce a fundamental wavelength of about1123 nm, The yellow cavity mirrors (e.g., M4, M5, and M6) may be highlyreflective at 1123 nm, but may suppress the reflectivity of other nearinfrared wavelengths. An additional optical filter F1 may be required inthe yellow laser cavity 222 to suppress competing lasing lines close to1123 nm. Part of the 1123 nm light within the laser cavity 222 may beconverted to about 561 nm by, for example, frequency doubling section224. This 561 nm (yellow) light may be extracted from the yellow lasercavity 222 by partial transmission through the yellow laser output foldmirror M5. Other wavelengths in the yellow spectrum may be used, andother types of laser sources may be used.

Laser sub-system 150 may include an extra-cavity 250 of laser sub-system150. Extra-cavity 250 may include an optical configuration 160, whichmay integrate focusing and steering optics, including the variouslenses, mirrors, and windows etc. described in detail below, to alignthe paths of independent laser beams from one or more laser cavities,such as cavities 220, 222 and 224, along a common optical axis 280, oronto a combined coaxial path. The extra-cavity portion 250 of the lasersub-system 150 may begin after the doubled frequency light passesthrough the fold mirror (e.g., M2, M5, M8) of laser cavities 220, 222and 224 respectively. The beams from laser cavities 220, 222 and 224 maybe collimated by lenses, for example, L1, L2, and L3, respectively, andmay then be channeled along common axis 280 with the paths of the otherbeams using one or more combiner mirrors (e.g., M10, M11, and M12).

For example, a red laser beam may be collimated by lens L1, and thenreflected by a combiner mirror M10, towards a first surface 281 ofmirror M11. The combiner mirror M10, in the current example, may reflectabout 659 nm light while transmitting about 1319 nm light to removeresidual fundamental wavelength radiation from the 659 nm beam. Thereflected beam, for example 659 nm light beam, may be referred to as the“illumination” or “treatment” beam, to be used to illuminate or treat aselected target. The angle of the combiner mirror M10 may be adjusted toalign the output beam parallel to the common optical axis 280 of theextra-cavity optics 250. After reflection from combiner mirror M10, thered beam may be passed through an alignment window, e.g., window W1.Alignment window W1 may be a rotatable glass substrate havingsignificant thickness and parallel surfaces, as is know in the art. Anincident beam that is passed through the alignment window may betranslated according to a selected thickness and angle, such that theoutput beam may be parallel to and shifted along common optical axis280, causing a displacement of the beam that is approximatelyproportional to the incident angle of the beam. The angle of window W1may be adjusted, for example, to center the path of the red beam on thepath of the yellow beam, at a second surface 282 of mirror M11, atyellow combiner mirror M11.

For example, the yellow laser beam may be collimated by lens L2, andthen reflected by the yellow combiner mirror M11, which, in the currentexample, may reflect about 561 nm light while transmitting about 1123 nmlight to remove residual fundamental wavelength radiation from the 561nm beam. Combiner mirror M11 may also transmit the 659 nm redillumination beam, which may have been aligned to have a path that is incommon with the yellow beam at the second surface 282 of combiner mirrorM11. The angle of the yellow combiner mirror M11) may be adjusted toalign the path of the yellow beam parallel to the path of the red beam.After reflection (yellow) or transmission (red) from yellow combinermirror M11, both the yellow and red beams may pass through an alignmentwindow W2. The angle of alignment window W2 may be adjusted to centerthe paths of the red and yellow beams on the path of the green beam, atan output surface of the green combiner mirror M12, in a similar way asdescribed above with reference to mirror M11.

For example, the green laser beam may be collimated by lens L3, and thenreflected by the green combiner mirror M12, which, in the currentexample, may reflect about 532 nm light while transmitting about 1064 nmlight to remove residual fundamental wavelength radiation from the 532nm beam. Combiner mirror M12 may also transmit the 659 nm red and 561 nmyellow illumination beams, which may have been aligned to have a paththat is in common with the green beam at the output surface of combinermirror M12. The angle of the green combiner mirror may be adjusted toalign the path of the green beam substantially parallel to the path ofthe red and yellow beams. After reflection (green) or transmission (redand yellow) from the green combiner, all three beams may pass through analignment window W3. The angle of alignment window W3 may be adjusted tocenter the paths of all three beams on the common optical axis 280 ofextra-cavity optics 250.

After the paths of the laser beams with their respective wavelengthshave been aligned to the common optical axis 280 of extra-cavity optics250, the paths of the beams pass through a fourth window denoted W4 toreach the optics sub-system 165.

FIG. 2B is a schematic illustration of optics sub-system 165 accordingto some embodiments of the present invention. The respective beams onthe common axis 280 may be passed through an optional computercontrolled moving attenuator denoted F2 to reduce the beam power whendesired. The respective beams may pass through one or more powermonitoring detectors (DET, DET-2), for example detectors 167 and 168,which may be, for example, a main photocell detector and a safetyphotocell detector, respectively, or other suitable detectors, to ensurethat the required calibrated power is delivered. Each detector channelmay include a mirror, for example a “pickoff” mirror (e.g., M13, or M14)that may reflect a small portion of the beams to a diffuser, such asdiffuser F3 and/or F4. Diffuser F3 and/or F4 may scatter light to aphotodiode, such as, for example, detectors 167 and 168. Detectors 167and 168 may be, for example, equivalent to main photocell 167 and safetyphotocell 168 (of FIG. 1B).

A safety shutter 170 may be positioned after power detectors 167 and 168to block or limit the duration of the illumination beams during, forexample, system start-up and testing. Safety shutter 170 may also blockthe illumination beams, for example, when system 100 is in “Standby”,when the emergency off switch is depressed, and/or when system errorsare detected. At a mirror M15, the incoming beams may be combined withan aiming beam 172, for example, a diode-aiming beam generated by lasersource DL-4. Mirror M15 may transmit the desired illuminationwavelengths (e.g., 659 nm, 561 nm, and 532 nm) and reflect aiming beam172, for example, at 635 nm. By adjustment of aiming beam combinermirror M15, aiming beam 172 may be aligned co-axially with one or moreillumination or treatment beams.

System 100 may enable directing of the laser beam output(s) to one ormore selectable delivery system optical ports, such as fiber ports 283and 284, to deliver laser energy to one or more laser delivery systems.A mechanical moving mirror M16 may be used to direct laser energy to aselected optical ports, e.g. ports 283 and 284. When delivering energyto port 283, for example, moving mirror M16 may not be placed in thebeam path, and the beam energy may pass over the mirror M16, through anobjective lens L4, to port 283. When delivering energy to port 284, forexample, moving mirror M16 may be placed in the beam path, and mayreflect incoming beams to a second mirror M17 in front of port 284.Second mirror M17 may direct the beams to the objective lens L5 of port284. Objective lenses such as L4 and/or L5 may be used to converge theaiming and illumination beams to produce a beam waist suitable forcoupling the laser energy into an optical fiber. The ports may beconfigured, for example, using a socket such as a format optical socket,for example a “smart nut”. Such a smart nut may be a custom SubMiniatureversion (SMA) connector, for example, as manufactured by Amphenol, 1Kennedy Ave, Danbury, Conn. 06810, which may provide a means for thelaser system to automatically identify the type of delivery deviceattached to each laser port. With this delivery device identification,system 100 may activate unique features specific to this delivery device(e.g., power settings, power limits, duration settings, fluencecalculators etc.). For example, a 906 SMA socket may be used, that maybe aligned to center the focused laser beams on the fiber connector ofthe various delivery devices that may be attached to ports 283 and 284respectively. In addition to the 906 SMA format optical socket, theoptical ports may read a resistance from contacts on the delivery deviceSMA “smart nut”. Various resistances may be used to encode the type andcharacteristics of the respective delivery devices attached to therespective optical ports.

FIG. 3, in conjunction with previous FIGS. 1A, 1B, 2A and 2B, is aflowchart illustrating an exemplary method for generating and deliveringbeams of different wavelengths from two or more DPSS laser sources. Ascan be seen in FIG. 3, at block 305 nominal light beams may be generatedby pumping one or more laser sources, such as pump diode lasers 212, 214and 216, using primary laser sections, such as 206, 207 and 208,respectively. At block 310 the nominal light beams may be frequencydoubled by frequency doubling sections 226, 227 and 228. At block 315the respective frequency-doubled beams may be passed through foldmirrors M2, M5, and M8 for each laser cavity 220, 222 and 224respectively. At block 320 the beam from each laser cavity may becollimated by a respective lens, L1, L2, and/or L3. At block 325 thepaths of the respective laser beams may be combined or aligned along acommon optical axis 280 by one or more combiner mirrors, e.g., M10, M11,and M12. At block 330 beams passing through the common optical axis 280may be attenuated by passing through a moving attenuator F2. At block335, the attenuated beams may be passed through one or more powermonitoring detectors, detectors 167, 168, to detect whether an outputbeam's power is at an acceptable level, relative to a predeterminedpower level. Such detection may be achieved by reflecting at least aportion of an output beam to a diffuser, e.g., F3, F4, by one or morepick-off mirrors M13, or M14, and by scattering a reflected portion ofthe beam from diffuser F3, F4, to pass the scattered light through atleast one photodiode, e.g., detectors 167, 168. At block 340 beams, forexample unwanted illumination beams, may be blocked out or limited by asafety shutter 170. At block 345 an aiming beam 172 generated by lasersource DL-4 may be aimed at a mirror M15, together with the illuminationbeam from laser cavities 220, 222 or 224, to align the aiming beam 172with the selected illumination beams. At block 350 the laser beams maybe directed to one or more delivery systems for delivery of laser energyto one or more selected targets.

Any combination of the above steps may be implemented. Further, othersteps or series of steps may be used.

Reference is now made to FIG. 4, which is a flow chart illustrating anaspect of an exemplary method for controlling laser output by the laserillumination system of FIG. 1. The method may include: At block 400,performing selection of a desired wavelength to be delivered. At block405 selecting a laser source to be activated, corresponding to theselected wavelength. At block 410 selecting laser exposure settings forthe selected wavelength (block 400), which may include parameters suchas power, exposure duration, and treatment intervals etc. At block 415activating the selected laser source to generate a laser beam with therequired wavelength. At block 420 receiving appropriate feedback from adetector, such as main detector 167, and processing the data received.For example, the actual power output may be compared to the desiredpower parameters. The laser output by the selected laser source may beadjusted, if necessary, according to one or more laser output powerparameters, for example, by altering the pump diode current to match therequired power level. At block 425, validating that the actual poweroutput is accurate, for example, by comparing safety detector results tothe results from the a detector such as main detector 167. Block 425 maybe executed simultaneously with block 420.

Any combination of the above operations may be implemented, and anynumber of the above operations may be implemented. Further, otheroperations or series of operations may be used.

The foregoing description of the embodiments of the invention has beenpresented for the purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed. It should be appreciated by persons skilled in the art thatmany modifications, variations, substitutions, changes, and equivalentsare possible in light of the above teaching. It is, therefore, to beunderstood that the appended claims are intended to cover all suchmodifications and changes as fall within the true spirit of theinvention.

1. A diode pumped solid state laser system, comprising: two or morediode pumped solid state laser cavities able to produce beams of two ormore respective wavelengths travelling in associated paths; a controllerto selectively control activation of at least one of the two or morediode pumped solid state laser cavities and to selectively controlassociated power levels of the produced beams of the at least one of thetwo or more diode pumped solid state laser cavities; and an opticalconfiguration to align the associated paths of said beams along a commonoptical axis.
 2. (canceled)
 3. The system of claim 1, wherein at leastone said laser cavities comprises a primary laser section and afrequency doubling section.
 4. The system of claim 1, wherein saidprimary laser section comprises a pump diode laser source.
 5. The systemof claim 1, wherein said optical configuration comprises at least onefold mirror.
 6. The system of claim 1, wherein said opticalconfiguration comprises one or more combiner mirrors to combine thepaths of at least two laser beams.
 7. The system of claim 1, comprisinga plurality of optical ports associated with an output of said opticalconfiguration.
 8. The system of claim 1, comprising at least onedelivery system to deliver at least one of said laser beams to a targetarea.
 9. The system of claim 1, wherein said two or more diode pumpedsolid state laser cavities are three diode pumped solid state lasercavities, able to produce beams of three respective wavelengths.
 10. Anillumination method, comprising: controlling activation of at least oneof two or more diode pumped solid state laser cavities and power levelsof beams produced by the at least one of the two or more diode pumpedsolid state laser cavities, the beams traveling in associated paths;aligning the paths of two or more diode pumped solid state generatedlaser beams having two or more respective wavelengths on a commonoptical path; and delivering at least one of said laser beams to atarget area.
 11. The method of claim 10, comprising: passing said two ormore laser beams through two or more respective fold mirrors; andcombining the paths of at least two said respective laser beams usingone or more combiner mirrors.
 12. The method of claim 10, furthercomprising delivering an aiming beam substantially along said opticalpath.
 13. The method of claim 10, comprising channeling said two or morerespective laser beams via one or more optical ports.
 14. The method ofclaim 10, comprising delivering said respective laser beams using one ormore delivery systems.
 15. An apparatus to combine the paths ofrespective laser beams of two or more wavelengths, comprising: acollimation lens to collimate at least two diode pumped solid statelaser generated beams of different wavelengths; and an opticalconfiguration to align the paths of the collimated beams along a commonoptical axis.
 16. The apparatus of claim 15, wherein said opticalconfiguration includes at least one combiner mirror.
 17. The apparatusof claim 15, comprising a moving attenuator to attenuate at least one ofsaid beams.
 18. The apparatus of claim 15, comprising at least onepower-monitoring detector to detect the power of at least one of saidbeams on said common optical axis.
 19. The apparatus of claim 15,comprising at least one pickoff mirror to reflect at least one or saidbeams to a diffuser.
 20. The apparatus of claim 15, comprising a safetyshutter to limit the exposure of said target to said beams.
 21. Theapparatus of claim 15, comprising an aiming beam to enable aiming ofsaid beam towards a target.
 22. The apparatus of claim 15, comprising atleast one optical port associated with said common optical axis.
 23. Theapparatus of claim 15, comprising at least one optical socket.
 24. Theapparatus of claim 15, comprising one or more laser delivery systems todeliver at least one of said beams to a target.
 25. A method to operatea laser illumination system at one or more selected wavelengths,comprising: selecting a desired wavelength to be delivered; selecting adiode pump laser source to activate; selecting laser exposure settingsfor the selected wavelength; and activating said selected laser sourceto generate a beam with a desired wavelength.
 26. The method of claim25, further comprising: processing feedback from a detector, for saidgenerated beam; and validating accuracy of the actual power output ofsaid generated beam.